Fabricating Complex Three-Dimensional Nanostructures with High-Resolution Conformable Phase Masks

Author(s): Jeon, Seokwoo, Jang-Ung Park, Ray Cirelli, Shu Yang, Carla E. Heitzman, Paul V. Braun, Paul J. A. Kenis, John A. Rogers

Journal: Proc. Natl. Ac. Sci. (2004) 101(34): 12428-12433.

Abstract:
High-resolution, conformable phase masks provide a means to fabricate, in an experimentally simple manner, classes of 3D nanostructures that are technologically important but difficult to generate in other ways. In this approach, light passing through a phase mask that has features of relief comparable in dimension to the wavelength generates a 3D distribution of intensity that exposes a photopolymer film throughout its thickness. Developing this polymer yields a structure in the geometry of the intensity distribution, with feature sizes as small as 50 nm. Rigorous coupledwave analysis reveals the fundamental aspects of the optics associated with this method; a broad-range 3D nanostructures patterned with it demonstrates its technical capabilities. A nanoporous filter element built inside a microfluidic channel represents one example of the many types of functional devices that can be constructed.